Heat exchange systems generally use a refrigerant to carry thermal energy between a temperature controlled environment and an ambient environment. Such systems generally include an external heat exchanger coil, an expansion valve, an internal heat exchanger coil, and a compressor, each fluidly connected to one another. In some heat exchange systems, the direction of refrigerant flow is reversible such that the heat exchange system can be used for either heating or cooling the temperature controlled environment.
Under certain operating conditions, moisture present in the ambient environment may freeze and accumulate on the external heat exchanger coil, and thereby reduce the efficiency of the heat exchange system. As a result, many heat exchange systems include a defrost controller configured to initiate a defrost cycle in the heat exchange system and melt the ice accumulated on the external heat exchanger coil. Some known heat exchange systems use a reversing valve to reverse the direction of refrigerant flow during the defrost cycle to flow relatively high temperature refrigerant through the external heat exchanger coil and melt the ice accumulated thereon.
Heat exchange systems manufactured by different heat exchange system manufacturers typically have different defrost modes, different reversing valve energizing modes, and/or other different settings which control operation of the heat exchange system. Known defrost controllers do not provide sufficient operability between heat exchange systems manufactured by different heat exchange system manufacturers. As a result, when a defrost controller in a heat exchange system needs to be replaced, the defrost controller is typically replaced with the same type of defrost controller used by the original heat exchange system manufacturer. Heat exchange system servicers are therefore required to stock numerous different defrost controllers, and also carry numerous different defrost controllers when servicing heat exchange systems. Suppliers of heat exchange system servicers similarly stock numerous different defrost controllers to meet the demands of the heat exchange system servicers. Accordingly, a need exists for a more satisfactory defrost controller.
This Background section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.